1. Field of the Invention
The present invention relates to an apparatus for image reading or processing which is able to discriminate whether an input image is a predetermined image.
2. Related Background Art
The technical development for hard copying, for example with copying machines, has been aimed at faithful reproduction of the original image, and as a result, there is now made available a high-quality copying machine which can provide a reproduced image excellent in color reproduction and not distinguishable from the original image. Particularly, the development of digital full-color copying machine has improved the quality of copied images to a level not distinguishable from the original image by human eyes, and has enabled one to obtain such copy within a short time with a simple operation.
However, 00 such image reproduction in a form very close to the original image could give rise to significant problems, as it may be abused for forgery of banknotes or other valuable securities. Existing image processing apparatus, such as copying machines, are powerless to detect and prevent such abuse.
The assignee of the present application already has disclosed technologies for preventing forgery of particular images in the U.S. Pat. Ser. No. 351,165, filed May 12, 1989 and in the new U.S. Patent Application based on the priority Japanese Patent Application No. 63-267198, filed Oct. 25, 1988.
The former discloses a technology for altering the image forming process in a case where the original image to be copied is identified as a predetermined particular image, and for altering the process according to the level of similarity to the particular image.
Also, the latter application discloses a technology for registering an image of which copying is to be prohibited by reading said image with a reader, and for renewing such registration.
However, such technologies still have room for improvement in the realization of the image processing apparatus capable of effectively preventing the forgery of particular images, particularly in the detection of particular image and in the image processing control in response to such detection.